Nelson hurt in Packers’ loss to Steelers

Aaron Rodgers and Ben Roethlisberger look ready for the regular season.

The immediate future for Jordy Nelson seems far more uncertain.

The Green Bay Pro Bowl wide receiver limped off with a potentially serious left knee injury in the first quarter of the Packers’ 24-19 preseason loss to the Steelers (1-2) on Sunday. Nelson landed awkwardly while trying to cut after making an 8-yard reception on Green Bay’s opening drive and did not return.

Rodgers completed 4 of 5 passes for 57 yards during two series of work for the Packers (1-1).

Roethlisberger played into the second quarter, connecting on 11 of 14 for 100 yards and a score.

49ers 23, Cowboys 6: Long black hair swinging from his helmet, 303-pound defensive lineman Mike Purcell intercepted Dustin Vaughan’s pass and returned it 37 yards for a touchdown to help San Francisco (1-1) beat Dallas (0-2) in Santa Clara, California.

Purcell, a practice-squad player in 2013 and for all but the final two games last season, provided the highlight again after his six-tackle day in an Aug. 15 loss at Houston.

Dallas avoided a shutout when fourth-string quarterback Jameill Showers threw an 8-yard touchdown pass to Nick Harwell in the waning moments.

Titans 27, Cardinals 14: Marcus Mariota turned in a clean performance in his home debut, Tennessee cornerback Perrish Cox returned an interception 24 yards for a touchdown and the Titans (1-1) beat St. Louis (0-2) in Nashville, Tennessee to spoil Rams coach Jeff Fisher’s return to town.

A week after Mariota was sacked, threw an interception, and lost a fumble that was returned for a touchdown, the No. 2 pick overall out of Oregon was 5 of 8 for 58 yards with no turnovers.

Nick Foles had a rough outing in three series for the Rams.

Quick kicks

Robert Griffin III returned to practice Sunday, three days after the Washington quarterback left the Redskins’ exhibition game against the Detroit Lions because of a concussion. Griffin fully participated in individual, 7-on-7 and 11-on-11 drills during the approximately two-hour session at Redskins Park. Griffin, who repeatedly wound up on the FedEx Field turf in the Redskins’ 21-17 home victory Thursday night, was sacked three times and fumbled twice in four possessions. … Browns quarterback Johnny Manziel cut his practice short Sunday after experiencing soreness in his right elbow and could be sidelined for a few days. Manziel has been bothered by a sore elbow for the past two weeks.